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Drug Safety Update - March 2014

The Medicines and Healthcare products Regulatory Agency (MHRA) has published Drug Safety Update for March 2014 (PDF).

This issue contains drug safety advice informing clinicians of a theoretical interaction between orlistat and antiretroviral HIV medicines. Orlistat may reduce the absorption of these medicines and as such reduce efficacy. It is recommended that orlistat is only used in patients taking antiretroviral HIV medicines after careful consideration. It is also recommended that individuals interested in purchasing orlistat (Alli®) over the counter should consult their doctor before starting treatment.

This section also reminds clinicians that St John’s wort interacts with hormonal contraceptives. Two Yellow Card reports have been submitted recently regarding women using the etonogestrel implant (Implanon® or Nexplanon®) who used St John’s wort and subsequently had an unplanned pregnancy. Clinicians are advised to tell women taking hormonal contraceptives for pregnancy prevention not to take herbal products containing St John’s wort.

The stop press section contains additional information about the recently announced restricted indications and new monitoring requirements for strontium ranelate in light of increased cardiovascular risks and also the new restricted use and monitoring requirements for methysergide in light of serious fibrotic reactions. Methysergide is currently only available in the UK via unlicensed imports. The stop press section also advises that the updated packaging design for dorzolamide/timolol (Cosopt®) preservative-free eye drops, which aims to prevent inadvertent eye injuries, is now available.

Finally, in other information, advice disseminated via the NHS Central Alerting System in January regarding combined hormonal contraception is clarified. Annexes sent with this alert recommend that women at higher risk of VTE use "a non-hormonal form of contraception" when it ought to have stated "that a different form of contraception should be used". This change indicates that progestogen-only contraceptives as well as non-hormonal methods are suitable options.

Action: Clinicians will find this publication to be a useful review of current issues in drug safety.